As shown in FIG. 1, the upper fork tubes 11 of the conventional bicycle shock-absorbing front fork main body 10 are fitted into the lower fork tubes 12, which are provided with a shaft support rod 13 for pivoting an arm-holding member 15 which has a brake shoe 14 and is capable of being actuated by a brake cable 17. The shaft support rod 13 serves as a fulcrum at the time when the brake shoe 14 is at work. In other words, the shaft support rod 13 is subjected to a backward thrust when the brake shoe 14 is engaged with the wheel rim, as illustrated in FIG. 2. As a result, the upper segments of the lower fork tubes 12 are acted on by a side thrust and a spin force. In order to stabilize the lower fork tubes 12, a support frame 18 is provided such that the support frame 18 is fastened with the upper segments of the lower fork tubes 12.
Such a shock-absorbing structure of the bicycle front fork as described above is not cost-effective and is rather timeconsuming in installing the structure.